People are advised to stay out of the saltwater at Chambers Creek Regional Park in University Place as a precaution after approximately 200,000 gallons of partially disinfected sewage was discharged into the water.

The incident, caused by a brief mechanical failure at the Chambers Creek Regional Wastewater Treatment Plant, occurred on Wednesday, Jan. 22.

“The effluent was fully treated, although a portion did not receive UV exposure during the disinfection stage due to a temporary system outage,” said Carl Every, Pierce County Public Works and Utilities sewer division manager. “We immediately took samples and determined we did not exceed our discharge limits. Our results show we were not in violation of our National Pollutant Discharge Elimination System (NPDES) permit.”

As a precaution, swimmers, waders, and boaters should avoid contact with the water at the park’s public beach, located off of Grandview Avenue, while the Tacoma-Pierce County Health Department conducts independent testing.

The advisory will be lifted when the Health Department verifies that bacteria levels in the water are normal.

Red “Closed” signs have been posted at the beach notifying people to stay out of the water until further notice as a precaution, although the beach itself remains open. Anyone who comes into contact with the water should wash well with warm, soapy water. Clothes should also be washed.

On Wednesday, the data systems at the plant that monitor the treatment process began experiencing problems. A technician doing normal system checks discovered that one of the three channels running through the UV disinfection system had been down for approximately 30 minutes and manually restarted that portion of the UV disinfection system.

The treatment plant notified the Department of Ecology on Thursday as required, and worked with the Tacoma-Pierce County Health Department on Friday, Jan. 24 to issue the water advisory as a precaution.